A cubic solid has two different atoms P & Q. Atoms P are present at comers and Q at the centre of the cube. What is the formal of unit cell ?

Explanation

To determine the formula of the unit cell for a cubic solid containing two different atoms P and Q, we will follow these steps:

### Step 1: Identify the positions of the atoms in the unit cell
In the given cubic solid:
- Atoms P are located at the corners of the cube.
- Atoms Q are located at the center of the cube.

### Step 2: Calculate the contribution of atom P
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